Liquid analyzing device

ABSTRACT

DEVICE FOR LIQUID ANALYSIS, THE LIQUID SAMPLES BEING CONTAINED IN WORKING TUBES, WHICH MAY COMMUNICATE WITH AUXILIARY TUBES CONTAINING AUXILIARY LIQUIDS BY MEANS OF A HOLLOW NEEDLE HAVING A LATERAL ORIFICE, WHICH PIERCES THROUGH AN AUXILIARY TUBE INTO A WORKING TUBE. THE LATERAL ORIFICE IS THEN LOCATED INSIDE THE AUXILIARY TUBE AND THE ORIFICE AT THE TIP OF THE NEEDLE IS LOCATED INSIDE THE WORKIND TUBE.

Jan. 30, 1973 J U N ET AL 3,713,717

LIQUID ANALYZING DEVICE Filed June 16, 1971 2 Sheets-Sheet l INVENTORS MICHEL JOSEPH AUPHAN JEAN ROBERT PERILHOU E EWQKW AGENT Jan. 30, 1 973 M. J. AUPHAN ET AL 3,713,777

LIQUID ANALYZING DEVICE 2 Sheets-Sheet 2 Filed June 16. 1971 [NVENTOR5 MICHEL JOSEPH AUPHAN JEAN ROBERT PERILHOU AGENT United States Patent 3,713,777 LIQUID ANALYZING DEVICE Michel Joseph Auphan, Courbevoie, and Jean Robert Perilhou, Bourg-la-Reine, France, assignors to US. Philips Corporation, New York, NY.

Filed June 16, 1971, Ser. No. 153,573

Claims priority, application France, July 1, 1970,

Int. Cl. G01n 1/14 US. Cl. 23-259 2 Claims ABSTRACT OF THE DISCLOSURE Device for liquid analysis, the liquid samples being contained in working tubes, which may communicate with auxiliary tubes containing auxiliary liquids by means of a hollow needle having a lateral orifice, which pierces through an auxiliary tube into a working tube. The lateral orifice is then located inside the auxiliary tube and the orifice at the tip of the needle is located inside the working tube.

The invention relates to a device for analyzing a plurality of liquid samples, each contained in a tube having an elastic wall, termed working tube, said device comprising at least one working space located between a stationary wall and a row of pressing feet adapted to be moved towarls the stationary wall and located opposite the stationary wall, said working space being adapted to accommodate each time on Working tube extending parallel to the row of pressing feet, the device comprising furthermore auxiliary tubes containing auxiliary liquids and also having an elastic wall, said auxiliary tubes being movable and being adapted to be moved one by one up to a small distance from the working tube contained in the working space, whilst for establishing a communication between the working tube in the working space and the near auxiliary tube a hollow needle having an orifice near its tip is provided.

Such a device is known from French Pat. of Addition No. 93,162. In the known device the working tubes are arranged parallel to each other on a conveyor belt. The auxiliary tubes are fastened also parallel to each other in cavities in a thick conveyor belt. Each auxiliary tube can be slipped out of its cavity until it is near a wonking tube. A hollow needle fastened to the auxiliary tube pierces the wall of the working tube, after which by means of pressing feet, which locally pinch the auxiliary tube auxiliary liquid is transferred through the needle.

to the working tube.

The known structure has the disadvantage that each auxiliary tube has to be provided with a hollow needle, so that the auxiliary tubes are expensive and have to be handled carefully.

The invention has for its object to provide a simple structure which is free of said disadvantages. For this purpose the device embodying the invention is characterized in that the needle 3 is axially displaceable through two opposite points of the wall of the auxiliary tube 2 and through the wall of the working tube 1, the needle having a lateral orifice 4 at a distance from the tip which is substantially equal to the distance between the axes of the tubes measured in the direction of the needle 3-.

In order to stilfen the needle in piercing the two tube walls and in order to close the needle orifices, if desired, the device according to the invention is preferably constructed so that inside the hollow needle a pin is provided, the length of which is at least equal to the length of the needle, whereas its diameter is substantially equal to the inner diameter of the needle, said pin being axially movable relative to the needle.

3,713,777 Patented Jan. 30, 1973 The invention will be described more fully with reference to the accompanying drawing.

FIGS. 1 and 2 show a working tube with pressing feet during the preparations required for transferring an auxiliary liquid to the working tube.

FIGS. 3 to 10 show the working tube of FIGS. 1 and 2 and an auxiliary tube communicating therewith during consecutive stages of the transfer of auxiliary liquid.

A working tube 1 is accommodated in the working space between a stationary wall 8 and a row of pressing feet P P P P P adapted to be moved towards the stationary wall 8. The number of feet may, of course, be different from five in accordance with the analysis to be carried out.

Each pressing foot has a free position and a Working position. In the free position (see, for example, P in FIG. 2) the pressing foot does not engage the .working tube 1. In the working position (see, for example, P in FIG. 2) the working tube is flattened between the pressing foot and the stationary wall 8 so that at the place of the pressing foot, the working tube is shut.

Parallel to the working tube 1 an auxiliary tube 2 is arranged (see FIGS. 3 to 10), which can communicate through a hollow needle 3 with the Working tube. Apart from an orifice (not shown) near the tip the needle 3 has a lateral orifice 4, whose distance from the needle tip is substantially equal to the distance between the center lines of the working tube 1 and the auxiliary tube 2. The needle 3 is arranged in the holder 5, which can be moved (by means not shown) in the direction of length of the needle.

Inside the hollow needle 3 a pin 6 is provided, the diameter of which is substantially equal to the inner diameter of the needle. The length of the pin 6 is at least equal to the length of the needle 3 so that the pin can fill out the whole internal space of the needle (see, for example, FIG. 3). The pin 6 then closes the orifice 4 and that near the needle tip, whilst it stiifens the needle in piercing the walls of the auxiliary tube 2 and the working tube 1. The pin 6 is axially movable relative to the needle 3 and the holder 5 and can be pulled out of the needle at least to an extent such that the orifice 4 is free.

The transfer of a dose of an auxiliary liquid from the auxiliary tube 2 to the working tube 1 is performed as follows:

By way of preparation all pressing feet P to P are moved into the working positions so that they close the working tube (see FIG. 1). Subsequently, one of the pressing feet (P in FIG. 2) is moved into the free position. Owing to the elastic properties of the wall of the working tube 1 the latter springs back at the place of the pressing foot P so that a cavity 7 is formed.

The needle 3 is then pierced through the auxiliary tube 2 and it penetrates into the working tube 1 at the place of the cavity 7 (see FIG. 3). The pin 6 is withdrawn so that the lateral orifice 4 is set free (FIG. 4). This results in that due to the capillary effect in the needle and due to the atmospheric pressure auxiliary liquid flows the auxiliary tube 2 into the cavity 7 until the latter is filled. Then the pressing feet P and P are moved into the free positions (FIG. 5) so that the cavity 7 is enlarged. In the same manner as described above this larger cavity is also filled with liquid. Subsequently, the pin 6 is inserted back into the needle 3 (FIG. 6) so that the orifice 4 is closed, after which the pressing foot P is moved into the free position (FIG. 7), so that the auxiliary liquid in the working tube is subjected to atmospheric pressure.

Then a given dose of the auxiliary liquid contained in the working tube as required for the analysis has to be separated. For this purpose, for example, the pressing foot P is moved into the working position, after which an accurately defined quantity of auxiliary liquid is located above P (FIG. 8). The excess quantity of auxiliary liquid available beneath the pressing foot P is removed as follows: first the pin 6 is withdrawn so that the orifice 4 is released (FIG. 9), after which the pressing foot P is moved into the working position, while the needle 3 is gradually withdrawn so that the auxiliary liquid flows back into the auxiliary tube 2. This finally results in the final position shown in FIG. 10. The liquids in the Working tube can then be mixed in known manner, after which the analysis proper can start.

In the manner described above auxiliary substances can be dosed with very great accuracy: with a dose of 3 for example, the deviation may be about 1%.

If the analysis requires more than one auxiliary liquid, the operation described above is repeated with the same working tube and a different auxiliary tube, whilst the same needle 3 may be used.

These operations are quite suitable for automatic control.

What is claimed is:

1. A device for analysing a plurality of liquid samples, each contained in a tube having an elastic wall, termed working tube, said device comprising at least one working space located between a stationary wall and a row of pressing feet adapted to be moved towards the stationary wall and located opposite the stationary wall, said working space being adapted to accommodate each time one working tube extending parallel to the row of pressing feet, the device comprising furthermore auxiliary tubes containing auxiliary liquids and also having an elastic wall, said auxiliary tubes being movable and being adapted to be moved one by one up to a small distance from the working tube contained in the working space, whilst for establishing a communication between the working tube in the working space and the near auxiliary tube a hollow needle having an orifice near its tip is provided, said needle being axially displaceable through two opposite points of the wall of the auxiliary tube and through the wall of the working tube, the needle having a lateral orifice at a distance from the tip which is substantially equal to the distance between the axes of the tubes measured in the direction of the needle.

2. A device as claimed in claim 1 further comprising a pin provided inside the hollow needle, the length of said pin being at least equal to the length of the needle, whereas its diameter is substantially equal to the inner diameter of the needle, said pin being axially movable relative to the needle.

References Cited UNITED STATES PATENTS 3,490,876 1/ 1970 Auphan et a1 23-253 R 3,547,781 12/1970 Guigan et a1 23-259 3,607,097 9/1971 Auphan et a1. 23259 MORRIS O. WOLK, Primary Examiner R. E. SERWIN, Assistant Examiner US. Cl. X.R. 

